Abstract: The epoxy core with low thermal conductivity makes it difficult for the side bushing of converter valve to dissipate heat, resulting in excessive temperature, which seriously endangers the safe operation of the bushing. Meanwhile, strict requirements should be met in the production process of the core body, which restricts the development of the localization of the bushing. In response to this problem, this paper proposes a valve-side bushing (referred to as air-cooled bushing) technology based on forced air cooling. The thermoelectric-fluid-structure coupling simulation model of the air-cooled bushing is established, and the temperature, current-carrying and transient characteristics of the air-cooled bushing are analyzed. On this basis, the ±800 kV valve-side air-cooled bushing prototype is developed and verified by tests. The results show that the air-cooled bushing technology can be utilized to effectively reduce the bushing temperature, improve the temperature uniformity, and increase the flow capacity by 45%. Therefore, this technology can be utilized to effectively solve the problem of overheating of the bushing, and it is one of the effective ways to improve the reliability of the bushing and complete the replacement of localization.